Conventional gas turbine engines include an annular combustor having a plurality of circumferentially spaced carburetors disposed in one and sometimes two domes positioned at the upstream end of the combustor. The combustor is mounted within an annular combustor casing and receives high temperature, high pressure air discharged by a compressor for mixture with fuel delivered by the carburetors and then ignited.
Typically, the fuel manifolds are mounted circumferentially about the exterior of the combustor casing with fuel stems penetrating the casing to convey fuel to the fuel injectors of the carburetors. The fuel manifolds feeding the individual fuel stems are necessarily large to accommodate their virtual 360.degree. extension about the casing periphery. Consequently, engine weight is increased due to the large diameter manifolds and elongated fuel stems. Additionally, the extensions of the fuel stems within the engine cause aerodynamic pressure drops as air flows through the outer liner passageway past the fuel stems.
To avoid these penalties, it has been proposed, as disclosed in the commonly assigned MacLean et al. pending application entitled "Gas Turbine Engine Fuel Manifold", Ser. No. 07/891,925 which is a continuation of Ser. No. 07/642,780, filed Jan. 18, 1991, to mount the fuel manifolds internally of the combustor casing. Aside from the high temperature problems addressed by this copending application, there are other important considerations such as the mounting of the internal fuel manifolds, the attendant mis-matches in thermal growths, the reliability of the fluid couplings in the manifold feed lines, and the potential for fuel leaks and spillage which could lead to engine fires.